Gas formation in landfills may last for a very long time, and contributes significantly to anthropogenic emissions of greenhouse gases through emission of methane. Greater knowledge is needed about how methane leakage occurs and for environmental and economic reasons, it is important to collect and recycle methane gas. The Sysav landfill at Albäck in Trelleborg, has since the end of 2008/2009 been closed after more than 50 years of activity. The project aimed to provide information on gas leaks, measuring methane emissions from landfill surfaces and to develop a general methodology for reducing methane leakage from landfills.

In this project, a handheld laser instrument known as "LaserMethane Mini" was used to scan for leaks sources.... (More)

Gas formation in landfills may last for a very long time, and contributes significantly to anthropogenic emissions of greenhouse gases through emission of methane. Greater knowledge is needed about how methane leakage occurs and for environmental and economic reasons, it is important to collect and recycle methane gas. The Sysav landfill at Albäck in Trelleborg, has since the end of 2008/2009 been closed after more than 50 years of activity. The project aimed to provide information on gas leaks, measuring methane emissions from landfill surfaces and to develop a general methodology for reducing methane leakage from landfills.

In this project, a handheld laser instrument known as "LaserMethane Mini" was used to scan for leaks sources. Field measurements with the laser instrument were supplemented by screw drilling in which samples were taken to analyze the surface layer properties, and determine the organic content of landfill waste. The purpose of the drilling was done in an attempt to find a correlation between the detected leakage sources and surface layer density and concentration of decomposed organic materials. Methane production of landfill waste can be affected by thicker coverage and layer density, resulting in drier waste with less gas production, but also the age of the deposition material is relevant.
The results from field measurements indicated that leakage at Albäck landfill consists primarily of point source emission, but areas with diffuse methane leakage from surfaces have also been detected. It has also been noted that leakage occurs frequently in connection with different recovery wells, pipelines and observation wells. Several point source emissions show that the methane levels are not constant and, instead, can pulsate in intervals with maximum and minimum flows and in intervals with no measurable flow at all. Areas showing greater sensitivity to methane leakage are slopes, slope crests and slope toes. Gas leaks are often linked to areas of dead vegetation or bare regions, and visible cracks in the surface layer. Influence of landfill top layer has proven to be of importance when thickness and soil cover permeability are combined.

Results from field measurements indicated that wind speed and wind behaviour affect the level of the methane gas, where the concentration of methane could increase or decrease with wind speed. The effect of meteorological factors such as atmospheric pressure and methane emissions are correlated has not been possible to establish. Based on collected weather data, the air pressure varied little and could possibly be the reason that no conclusions can be drawn.

Determination of organic content shows that it is generally a higher content of combusted coal from younger cells. Drilling tests also showed that different depths gave varying weight losses, which is probably due to unique decomposition environments.
Completed seals at vulnerable point leakage, showed good results immediately after the first measurements, but later inspection demonstrated that several sealed objects have been exposed to unexpected high pressures. Any improvements in gas collection system at the landfill after sealed objects have not been able to establish. (Less)

@misc{2278498,
abstract = {Gas formation in landfills may last for a very long time, and contributes significantly to anthropogenic emissions of greenhouse gases through emission of methane. Greater knowledge is needed about how methane leakage occurs and for environmental and economic reasons, it is important to collect and recycle methane gas. The Sysav landfill at Albäck in Trelleborg, has since the end of 2008/2009 been closed after more than 50 years of activity. The project aimed to provide information on gas leaks, measuring methane emissions from landfill surfaces and to develop a general methodology for reducing methane leakage from landfills.
In this project, a handheld laser instrument known as "LaserMethane Mini" was used to scan for leaks sources. Field measurements with the laser instrument were supplemented by screw drilling in which samples were taken to analyze the surface layer properties, and determine the organic content of landfill waste. The purpose of the drilling was done in an attempt to find a correlation between the detected leakage sources and surface layer density and concentration of decomposed organic materials. Methane production of landfill waste can be affected by thicker coverage and layer density, resulting in drier waste with less gas production, but also the age of the deposition material is relevant.
The results from field measurements indicated that leakage at Albäck landfill consists primarily of point source emission, but areas with diffuse methane leakage from surfaces have also been detected. It has also been noted that leakage occurs frequently in connection with different recovery wells, pipelines and observation wells. Several point source emissions show that the methane levels are not constant and, instead, can pulsate in intervals with maximum and minimum flows and in intervals with no measurable flow at all. Areas showing greater sensitivity to methane leakage are slopes, slope crests and slope toes. Gas leaks are often linked to areas of dead vegetation or bare regions, and visible cracks in the surface layer. Influence of landfill top layer has proven to be of importance when thickness and soil cover permeability are combined.
Results from field measurements indicated that wind speed and wind behaviour affect the level of the methane gas, where the concentration of methane could increase or decrease with wind speed. The effect of meteorological factors such as atmospheric pressure and methane emissions are correlated has not been possible to establish. Based on collected weather data, the air pressure varied little and could possibly be the reason that no conclusions can be drawn.
Determination of organic content shows that it is generally a higher content of combusted coal from younger cells. Drilling tests also showed that different depths gave varying weight losses, which is probably due to unique decomposition environments.
Completed seals at vulnerable point leakage, showed good results immediately after the first measurements, but later inspection demonstrated that several sealed objects have been exposed to unexpected high pressures. Any improvements in gas collection system at the landfill after sealed objects have not been able to establish.},
author = {Bjerg, Benjamin},
keyword = {Lasermethane Mini,glödförlust,metangas,deponigasläckage,avfall,Trelleborg,Sysav,loss on ignition,methane gas,landfill gas leakage,waste},
language = {swe},
note = {Student Paper},
series = {Examensarbeten i geologi vid Lunds universitet},
title = {Metodik för att förhindra metanemissioner från avfallsdeponier, tillämpad vid Albäcksdeponin, Trelleborg},
year = {2011},
}